Yes, the widget would actually drain constantly the battery, but I've planned for the next release configurable refresh times and also a option to fetch data only over WiFi connections for those concerned with mobile bandwidth usage. The app also can show the unseen facebook notifications on user demand (via the launcher icon), so it is still useful for users with vital requirement about battery life. I will try my best to get it as configurable as possible, so any suggestions are welcome and will be considered for release